Here the cutting lines are set by symbols of package marvosym.
Because the cutting line chars contain already three dashes and fixed spaces, using \(c,x)leaders is a bit tricky. There should not be an additional space before or after a cutting line symbol inside the cutting line.

Because the line width is not a multiple of the cutting line symbol, the first line adds the remaining space at the left and right side of the cutting line.

The second line allows the cutting line to get a little outside the text width.

The third uses the other symbol set of package marvosym.

The fourth example horizontally scales the cutting symbols in the middle to fill the available space exactly.

I have done this once before. What I did is something like the one below. There some more scissor symbols with the The Comprehensive LaTeX Symbol List. It is not very good but it does the job with a little tweak here and there.

I have included the showframe option to the geometry package to show where the dashed lines stop. At this point, I don't have a way of saying \tikz \draw [dashed] (0,0) -- (end of text width,0); If somebody has an idea may be the command \Cutline can be made better.

Update (September 11, 2012) I am just adding the following code for closure to the TikZ possibilities for this problem. I put two of them here.

Finally, I fully agree with alexurba's statement about a lot of fuss about a dashed line that has to be cut anyway. That gave me my fill of laugh this morning. I would prefer my first solution anytime just to get the problem done away with in a matter of seconds. But alexurba's first solution is the least hackish and gets the job done very satisfactorily. Let me just say that this enterprise made me learn a lot about TeX in general.